[ci skip]

- Made all sentences to end properly
[ci skip]

- This change is made as the behavior for `:message` proc was changed in
  https://github.com/rails/rails/pull/24119.
- Also check
  https://github.com/rails/rails/pull/24431#issuecomment-206106790 for
  reference.

Adds changelog headers for beta3 release

We will support only Ruby >= 2.1.

But right now we don't accept pull requests with syntax changes to drop
support to Ruby 1.9.

[ci skip]

Most recent change should be moved to the top

In Active Record Querying guide, currently `Merging of scopes` section uses a concept of default scope in its example before it is introduced in the following section titled `Applying a default scope`.

It makes more sense to switch the ordering to introduce default scopes (`Applying a default scope`) first and then go into `Merging of scopes` section where it is used.

Remove 4-1 related entries from master [ci skip]

[ci skip]

Is it more suitable that using ```<th colspan="3">``` instead of three empty ```<th>```? It is simple, but what i am missing about it?

Change repetitive th tags to use colspan attribute

Update CHANGELOG.md

Update CHANGELOG.md

moving changelog note to unreleased section

New beauty pages(404, 422, 500)